MODEL: ACME No. 4 MICROSCOPE FOR PHYSICIANS' USE

DATE: after 1885

MAKER: JOHN W. SIDLE

SIGNED: Queen & Co., Phila

SERIAL NUMBER: NONE

DESCRIPTION:

This Lister limb microscope, which is well made, is supported by a heavy tripod. It has coarse focusing by straight rack and pinion, and fine via long lever. It is signed in script on the stage: Queen & Co, Phila. The unusual feature is the Placement of the fine focus knob under the arm instead of above. At first it seems this has no clear advantage, but in reality it made it closer to the table and therefore the user could adjust the fine focus while resting the remainder of their arm on the table, which meant it was easier to avoid vibration. This feature was popularized on the Nelson models by Baker, one of which is in this collection and can be seen here. There were
relatively few American or even European microscopes with this location of the fine focus at the time. The microscope has a swinging tailpiece carrying a gimballed planoconvex mirror. The vertical position of the mirror on the tailpiece is adjustable via a slot in the tailpiece in which the mirror support rides.
The stage is thin, and this together with the swinging tailpiece allows for very oblique illumination. This would help visualize objects with a refractive index close to the medium they were in. The tailpiece can swing above the stage to allow
illumination of opaque objects. There are two thin removable stage clips which fit on narrow posts which fit through the stage. A wheel of apertures under the stage can be completely swung out of the optical axis. This example
comes with a double nosepiece, two objectives and one ocular. The double nosepiece is signed Queen & Co., PHILA. The ocular is unmarked. One objective, of silver-color metal is signed National, Germany, 5:1, NA=0.10. The second objective is signed Queen, Bacteriological,1.12, HOMOG. IMM. 1.35 N.A. There is an uncalibrated drawtube.

HISTORY OF ACME MICROSCOPES

The ACME brand originated with John W. Sidle & Company. The company was based in Lancaster, PA from 1880-1891. It grew out of Sidle and Poalk. Sidle and Poalk made their first
microscope about August 1879, and their first production microscopes starting in 1880. Although they initially used several agents, they quickly settled on James Queen & Company as their sole agents in 1881.
This microscope was first brought out when Queen was already sole agent. As one can see from the ad pictured here, it was advertised as a stand for the use of physicians.

The company existed under the following names during the approximate dates listed: